Paul Grinnell

High tech radar planes have been used to carry out a unique survey of thousands of kilometres of overhead power lines across the east of England.

The multi-million pound survey of 34,000 kilometres of overhead cables is thought to be the first and largest of its type.

How the survey shows those overhead cables that are at risk.

The computerised results will give engineers a 3D desktop view of those overhead cables at risk of being brought down in high winds.

The three-month long survey was carried out by UK Power Networks.

The highly accurate data has enabled the company to devise a three-year tree cutting programme in areas where tree branches could touch or damage cables in high winds.

The radar plane illuminates targets with a laser and analyses the reflected light, revealing the exact distance of vegetation from overhead lines.

UK Power Networks, which owns and operates the electricity networks in the East of England, London and the South East, teamed up with solutions specialist ADAS and aerial photography firm Bluesky to begin work on the survey in July last year.

Three fixed-wing aircraft mapped the 34,000 kilometres of overhead lines over three months.

The information has been incorporated into a 3D web portal which can be viewed from desktop computers enabling UK Power Networks employees to carry out ‘virtual patrols’ of the network.

A UK Power Networks spokeswoman said: “This will save time and reduce the risk to employees who would otherwise have to carry out foot patrols, sometimes across difficult terrain including physical barriers such as rivers, ditches, livestock and numerous other potential hazards.”

Nigel Hall, head of service development at UK Power Networks, said: “This innovative multi-million pound project is of immense benefit to our customers and to the company.

“The risk-based tree-cutting programme will help reduce tree-related power cuts for customers, with the additional benefit that it could be carried out without any disturbance to local landowners because it was done from the air rather than on foot.

“As a company it will help us get best value from our £19 million annual tree cutting budget, and the web portal will mean staff can carry out ‘virtual patrols’ from their desk, saving them time and reducing the potential hazards if they had to walk the lines themselves.”

Roy Dyer, head of arboriculture in ADAS, said: “This has been a ground breaking contract.

“The combination of Bluesky’s technical ability and ADAS’ consultancy experience in managing vegetation near overhead lines enabled us to successfully deliver this challenging contract and improve the management and resilience of the overhead lines owned by UK Power Networks.” Rachel Tidmarsh, managing director of Bluesky, said: “Prior to commissioning the LiDAR and aerial mapping project, UK Power Networks undertook regular manual surveys as part of its assessment of network resilience.

“But the capture of LiDAR and associated aerial photography for the entire catchment area allows for evidence-based decision making and long term planning, and provides a proven solution for other network operators.”